Electrocution animal trap with a sender

ABSTRACT

An electrically powered rodent trap which includes a surveillance system for remote surveillance of the trap so that the trap may be operated without being attended to. A rodent which enters into the trap is killed by means of electrocution electrodes. The dead rodent is automatically dispatched from the trap, e.g. by a trapdoor, into a container or reservoir beneath the trap. The number of electrocutions and possible other data is stored by an electronic system incorporated in the trap and a signal is sent out, either by request from an external unit, or automatically to an external unit. A city rodent exterminator is capable of monitoring the status of the trap from an office location and thereby effectively tend to the trap or to a series of traps.

FIELD OF THE INVENTION

The present invention relates to a device for trapping and dispatchingsmall animals such as rats and mice through electrocution. Inparticular, the invention relates to a trap which can operate withoutbeing attended to.

DESCRIPTION OF PRIOR ART

The extermination of noxious animals is a well-known problem. In acommon approach the noxious animals are captured and killed in a trap.Several types of traps have been developed. The present invention dealswith a trap, wherein the executing means Is electrocution. In anelectrocuting trap the animal is killed by an electrical current that isdrawn through the body of the captured animal. Several types ofelectrocution traps have already been described, for example in thepatents U.S. Pat. No. 1,038,902; U.S. Pat. No. 5,918,409; U.S. Pat. No.5,949,636 and in the application FR 2 758 435-A1. In such traps a baitor lure is placed inside a housing with one or more entrances. Betweenthe entrance(s) and the bait a configuration of electrodes is present.The inside of the trap is designed in such a way that, if an animaltries to reach the bait, the animal inevitably touches the electrodesand thereby gets electrocuted.

None of the previously described traps, however, deal with the situationwhere regular control of the traps Is Inconvenient. Such situations canbe encountered If the trap Is located at a place, which Is difficult toaccess. Or, If a large number of traps are In operation, e.g. in acity-extermination program, where a network of traps are placed in asewer system. Surveillance of such a trap system requires considerableefforts, if all traps have to be monitored by subsequently checking alltraps one at a time.

DESCRIPTION OF THE INVENTION

In a first embodiment, the above mentioned problem has been solved bythe present invention by providing an electrically powered animal trap,which comprises

a set of electrodes for electrocution of the animal, and

means for communicating a surveillance signal between the trap and anexternal surveillance unit.

Due to the means for communicating a surveillance signal between a trapand an external unit, the keeper of the trap may know the condition ofthe trap without direct inspection of the trap. The trap may thus beleft unattended for a long period time, where the trap keeper can restassure, that the trap is fully operational.

The trap may comprise a bottom section with an upwardly extendingsidewall, a top section, and at least one entrance. The entrance may beeither in a sidewall, in the top section of the trap, in the bottomsection of the trap, or anywhere else. Upon entering the trap, theanimal enters a chamber, where a bait or lure may be placed in theopposite side of the chamber. The set of electrodes may comprise atleast two electrodes, e.g. placed between the entrance and the endsection where bait can be placed. The bait may be a liquid dripping in acontrolled way, which ensures a continuous supply of strong scent, itmay be In the form of dry pills or tablets, it may be food, or it may bea scent means. A bait storage arrangement may be provided, this mayenable automatically feeding the bait to a trough, and furthermorecontrol the flow of the bait from a storage to ensure optimal dosing.The surface of the electrodes may be rough. e.g. by adhering metal orplastic shavings to a metal plate in any conventional way, e.g. plasticcomposites Incorporating metal conductive wires or shavings. Anotherpossibility for making the electrode surfaces rough, is by using powdermetallurgy. However, smooth surfaces of the electrodes may also beprovided. In case three electrodes are used, the electrodes may beinterconnected in a way such that a first of the electrodes is connectedto a second of the electrodes and wherein a third of the electrodes iselectrically insulated from the first and second electrodes. A smallvoltage up to 4,5 V DC may be maintained between the two firstelectrodes and the third. The source may be a small accumulator, such asa 12 V motorcycle battery. An electronic circuit (a sensor circuit) maybe adapted to detect a leak current between the first and the thirdelectrode by detecting the presence of a finite resistance. This willhappen when an animal is touching electrode 1, at the same time as it istouching electrode 3. A high-voltage potential difference between thefirst and the third electrode should then be generated by an additional“power electronics”, which can be incorporated with the sensor circuit.The result is that the animal is electrocuted. The high-voltagepotential may be in the form of a continuous voltage maintained for apredefined time, or it may be in the form of a series of pulses. The useof pulses may be advantageous, as the animal may be killed faster andless painfully. These pulses may have the form of steps, where each stepcomprises different voltages kept for different time periods. The pulsesmay also be In the form of a sinusoidal wave, or it may be a series ofshort pulses. The electronic circuit may be made in a versatile waywhere these aspects can be adjusted electronically. Alternatively, onlytwo electrodes may be used.

The trap may comprise additional or different means for detecting thepresence of an animal by equipping the trap with a weight sensitivedetector, a motion sensitive detector, which may be achieved by usingone or more Infrared sensors, or a lever arm. These means may be addedin order to Increase the certainty that an animal is present In thetrap, before the high-voltage potential is generated, or they may beused as alternative means for detecting the presence of an animal.

The trap may be equipped with an exit for removing the electrocutedanimal into a receptacle. This receptacle may be an open receptacle as asewer or a small stream of water into which the dead animal may bedumped by e.g. using a trapdoor in the bottom of the trap. Toaccommodate a trap in such a situation, the trap may be equipped withlifting means to lift up the trap. The lifting means may be one or morelegs that are adjustable in length, for example telescopic legs, i.e.legs where a single or a series of thinner legs are sliding Inside athicker leg, and where a specific length can be maintained by a fixingmeans. The adjustment of the length of these legs can be facilitated byusing pressurized gas in a similar manner as with office chairs. Thereceptacle may likewise be a sealed container on top of which the trapis fastened. The containermay be equipped with a bag In which the deadanimals are collected. A bag will ensure easy and hygienic emptying ofthe trap as no physical contact with the dead animals is needed. Thereceptacle may contain a chemical bath for dissolving the animal.

The trap is fully automatic and controlled by the electronic circuit.The exit can be actuated either electrically, hydraulically,pneumatically, mechanically or by any combination of these. For examplea trapdoor where the locking-unlocking is an electromagnetic tap whichunlocks the trapdoor when the electrocution has finished. The trapdoorcan be fastened to the trap by a pivotal hinge at one side such that thedoor opens upon the weight of the dead animal, and tips back due to acounter weight. In another design the trapdoor Is also attached at oneside with a pivotal hinge, but in this case the opening and closing iscontrolled by a motor which unrolls and rolls up a piece of string. Itis also possible to place the hinges at opposite sides of the trapdoor,such that the trapdoor tips around an axis perpendicular to the axisaround which, the trapdoor tip when the hinges are places in the sameside of the trapdoor.

As the trap may be raised above the surroundings, an entrance ramp maybe needed. The ramp may be constructed in wood. But it may likewise beconstructed in plastic, stainless steal, nickel or any suitablematerial.

As the inside of an electrocution trap may be dangerous to touch, a tubeor a flexible hose may be mounted in front of the trap entrance. Byusing a bent tube (or a flexible hose), e.g. an s-form, an elbow form ora zigzag form, a child will not be able to get its arm Inside the trap.A trap which has such a mount placed in front of the entrance istherefore a lot safer to place in areas where children may play thanother types of traps. The entrance may also be equipped with a clippingmeans, thereby enabling to clip on and use any suitable material asentrance.

A battery can only supply a limited number of electrocutions before itneeds to be recharged. The trap may therefore be equipped with a poweradapter that allows connection directly to a power grid. Some traps maybe placed at locations where it is not possible to directly connect thetrap to a power grid. In this case the trap can be equipped with achargeable battery.

The trap may be able to stand flooding or high water levels if, e.g., itis located in a sewer. This may be achieved by embedding the electronicsin a waterproof housing, and furthermore by Incorporating a waterdetector that may transmit an electronic signal, e.g. in the case thewater level rises above a predetermined level. The electronic circuitmay be adapted to react in response to a signal from the water detector,by disabling the generation of the high-voltage potential. The waterdetector may comprise a timer detecting at predetermined time intervalwhether or not high voltage generation may be performed, or whether ornot it may be safe to switch on the electronics.

The electronic circuit could comprise means for storing anidentification code for the trap, and/or information relating to thenumber of captured animals, the remains of the bait, and the batterycondition. A display could be included in the electronic circuit, suchthat the above mentioned trap information may easily be read-out. Theelectronic circuit could furthermore comprise means for sending out awireless electromagnetic surveillance signal that may be received andread by an external unit. The signal may comprise the above mentionfeatures and may only send out upon receiving a request signal from theexternal unit, thereby avoiding draining the battery. A surveillancesignal may also automatically be sent out in the case of a capture, inthe case of low battery power or in the case of loss of bait. Thesurveillance signal may be any electromagnetic signal, such as aradio-signal, or a signal around 2,4 GHz which is the Bluetooth standardfrequency, or a signal in the low frequency domain, such as few hundredKHz. The trap may additionally comprise means for determining thegeographical position of the trap. This may be achieved by incorporationa global positioning system devise (GPS), a mobile positioning systemdevice (MPS), such technology has been demonstrated by the Swedishcorporation Ericsson, or a Nordic Mobile Telephone (NMT) device. Thesurveillance signal can therefore further comprise the position of thetrap. The electronic circuit may also be equipped with a means forreceiving a command signal send out by the external unit. This would beuseful if, for example, the trap is further equipped with a sizeadjustable entrance opening.

Above, only the situation of a single trap is described. An ensemble oftraps may be monitored by a software program adapted to storeinformation on the identity code, the position, etc., of the Individualtraps in the network. The software should collect information about thenumber of captures, the condition of the bait, and the current power onthe battery. A trap keeper could then fast obtain an overview of thetraps that are needed to be tended to.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, a preferred embodiment of the invention will bedescribed with reference to the drawing In which:

FIG. 1A and 1B are 3D cut of preferred embodiments of the invention,

FIG. 2 is an example of a voltage diagram,

FIG. 3A and 3B are preferred embodiments of a trapdoor,

FIG. 4 illustrates the invention in connection with a closed receptacle,and

FIG. 5 illustrates the invention mounted In a sewer.

DETAILED DESCRIPTION OF THE FIGS

In FIG. 1A, a 3D cut of a preferred embodiment of the present inventionis presented. The trapping chamber is Inside a housing which comprisessidewalls 1, a top 2 and a bottom section 3,4. The access to thetrapping chamber is an opening in one end of the trap housing. Theentrance is not shown, but it could be an opening in a wall adjacent tothe sidewall 14. The bottom section 3, 4 comprises two parts, one part 3which is fixed with respect to the housing as a whole, and another partwhich is movable. The movable part 4 constitutes an exit, hereillustrated as a trapdoor that opens in a downward direction. A set ofelectrodes comprising a first electrode 5, a second electrode 6 and athird electrode 7, are placed sequentially between the entrance and thesection where the bait 8, 9 and 16 is placed. From the bait reservoir 9,a scent-liquid is dripping into a small bowl 8. The bait reservoir maybe re-filled from outside the trap 16, as the reservoir protrudesthrough the top section of the trap. The power source of the trap is a12 V DC battery 10, placed on top of the trap. An electronic circuits 11is also placed on top of the trap. The electronic circuit includes ameans for communicating a surveillance signal. The surveillance signalis transmitted through the antenna 15. The opening and closing of thetrapdoor is actuated by a small motor 12 adapted to unroll and roll up astring in order to open and close the trapdoor.

The electronic circuit 11 comprises:

-   -   1. an electronic-print card with a microprocessor, a sensor        circuit, a “power electronic” to drive the motor and the high        voltage generator,    -   2. a motor to remove the animal from the trap chamber,    -   3. a display, and    -   4. a transmission system to remote read-out.

The sensor circuit is set to detect a leak current between the firstelectrode 5 and the third electrode 7, alternatively, between the secondelectrode 6 and the third electrode 7, by detecting a finite resistancebetween the electrodes. It can be adjusted electronically to register aresistance between 2 kΩ and 500 kΩ. The electrodes are kept at apotential of maximal 4.5 V DC between captures. In case of a detectionof a finite resistance between the first electrode 5 (or the secondelectrode 6) and 7, an electrocuting high-voltage potential is generatedbetween the same electrodes. The duration of the high-voltage potentialcan be adjusted electronically from 100 ms and up to permanent, with anoutput voltage between 500 V and 4 kV, and a transmitted power between100 mW and 25 W. The potential change uses that the inductivity in thetransformer when the period for the high voltage transformer is short.The duration is controlled by the microprocessor. The power in theelectrocuting-process is changed by changing the duty-cycle of thevoltage transformer, the total power admitted is thereby controlled.Also the electrocuting voltage can be varied, one example is given inFIG. 2. The details of the variation in the voltage difference can befurther elaborated upon using experience gained in experiments. Thepower-electronics control the motor, both with respect to speed, andwith respect to the time the exit remains open. A circuit can be addedwhich register when the motor stalls. A display shows the number ofelectrocutions, the remaining amount of the bait as well as the currentvoltage on the accumulator. The transmission system should be of thewire-loop principle, as this does not require broadcasting approval.Furthermore, this type of system works at low frequencies and can beused to transmit through earth and water.

In FIG. 1B, the trap as described in connection with FIG. 1A is slightlymodified. Here the bait reservoir 9 and a the small bowl 8 arepositioned in the central region of the trap. The presence of an animalis detected using an infrared sensor 100, and only two electrocutingelectrodes 101, 102 are used.

FIG. 2 gives an example of the voltage difference between firstelectrode 5 and the third electrode 7, or between electrode one 101 andtwo 102, versus time during the electrocuting process. At t=0 theelectrocuting voltage difference is generated. At t=t₁ the voltagedifference drops to a predefined level which is kept until t=t₂ wherethe voltage difference Is raised until a new pre-defined level. Att=t_(end) the voltage difference is set to zero.

FIG. 3A shows a second embodiment of the trapdoor 4, where instead ofusing a motor 11 and a string 13, the actuation of the trapdoor is anelectromagnetic switch 30 adapted to open upon a signal from theelectronic circuit 11. Due to the weight of the electrocuted animal, thetrapdoor opens by pivoting around a pivot tap 31, and closes afterrelease of the animal due to counter weights, here exemplified by athreaded bolt 33 and a nut 32.

In FIG. 3B and 3C a third embodiment of the trapdoor is shown. Here asolenoid 202 Is used to open and close the trapdoor. The solenoid may befixed to the trap using fixation means 200 and 201. By activating thesolenoid, rod 203 Is pulled into the solenoid, which through amechanical coupling to the trapdoor, opens the trap door, as shown InFIG. 3C. Using a solenoid may e.g. increase the control of the trapdoor.For example it may be possible to shake the trapdoor to make sure theanimal has fallen off, or to clear the trapdoor from debris or dirt onthe electrodes or the trapdoor in general.

FIG. 4 and 5 show two examples of trap set-ups. In both Figs. the trap20 is raised above the surroundings, and access to the trap chamber isensured by a ramp 21. In FIG. 2 the trap is placed on top of areceptacle 22, into which the animals are dumped after theelectrocution. Where FIG. 4 present a trap set-up that can be used inmany different locations, e.g. a store-house, a barn or a field, FIG. 5envision a special case where the trap is placed directly above a sewerstream. In this situation the sewer it-self is used as a receptaclewhere the animals are dumped directly into after electrocution. The trapis fastened in the sewer by using length adjustable legs 23. In FIG. 5the trap is positioned along the sewer, however, the trap may also bepositioned so that it bridges the water stream, i.e. positioned rotated90 degrees with respect to the one shown.

1. An electrically powered animal trap, which comprises a set ofelectrodes for electrocution of an animal, and means for communicating asurveillance signal between the trap and an external surveillance unit.2. A trap according to claim 1 further comprising a bottom with anupwardly extending sidewall, a top section, at least one entrance, andan exit.
 3. A trap according to claims 1 wherein the trap defines achamber between an entrance and an end section, which end sectionsupports arrangement of bait.
 4. Amended) A trap according to claims 1wherein the electrodes are arranged sequentially in the direction of thechamber.
 5. A trap according to claims 1 further comprising means forlifting up the trap.
 6. A trap according to claim 5, wherein the meansfor lifting comprises at least one leg.
 7. A trap according to claim 6wherein the at least one leg is adjustable in length.
 8. A trapaccording to claim 7 wherein the adjustment of the length is actuated bypressurized gas.
 9. A trap according claims 6 wherein the legs aretelescopic legs.
 10. A trap according to claims 1, further comprising areceptacle for storing the electrocuted animals.
 11. A trap according toclaim 10 wherein the receptacle and the trap is sealed.
 12. A trapaccording to any of the preceding claims further comprising anelectronic circuit including at least one micro processor, wherein theelectronic circuit is adapted to generate the high-voltage potentialfrom a low voltage power source upon detection of an animal.
 13. A trapaccording to claim 12 wherein the animal is detected by an electronicdetector connected to the electronic circuit.
 14. A trap according toclaim 13 wherein electronic detector is adapted to detect motion of ananimal.
 15. A trap according to claim 13 wherein the electronic detectoris adapted to detect weight of an animal.
 16. A trap according to claims12 wherein the high-voltage potential is generated in pulses.
 17. A trapaccording to claim 16 wherein the pulses are in the form of a sinusoidalwave, a step pulse or a series of pulses.
 18. A trap according to claims1 wherein the set of electrodes comprises at least 3 electrodes.
 19. Atrap according to claims 1, wherein the surface of the electrodes isrough.
 20. A trap according to claim 19 wherein the roughness of thesurface is provided by adhering metal shavings to a metal plate.
 21. Atrap according to claims 18 wherein a first of the electrodes isconnected to a second of the electrodes and wherein a third of theelectrodes is electrically isolated from the first and secondelectrodes.
 22. A trap according to claim 21 wherein the electrocutingis obtained by generating a high-voltage difference is a low voltage,high capacity DC-battery.
 23. A trap according to claim 12 wherein thepower source for generating the high-voltage difference is a lowvoltage, high capacity DC-battery.
 24. A trap according to claim 22wherein the high-voltage potential is generated upon detection of a leakcurrent through the animal between the first and second electrode.
 25. Atrap according to claims 1, further comprising a lever arm for detectingthe presence of an animal.
 26. A trap according to claim 25 where thehigh-voltage potential is generated when an animal moves the lever arm.27. A trap according to claims 1 further comprising an entrance ramp.28. A trap according to claim 27, wherein the ramp is made from amaterial selected from the group consisting of: wood, plastic, stainlesssteal and nickel.
 29. A trap according to claims 1 further comprising amount at the entrance such that an additional section can be mounted infront of the entrance.
 30. A trap according to claim 29 wherein themount section comprises an entrance tube.
 31. A trap according to claim30 wherein the tube has at least one bent.
 32. A trap according to claim30 wherein said tube possesses one of the following shapes: an s-form,an elbow, and a zigzag.
 33. A trap according to claim 1 furthercomprising a power adapter that allows direct connection to an existingpower network.
 34. A trap according to claim 33 wherein the poweradapter is compatible with an input voltage with an AC-amplitude between110 to 380 V.
 35. A trap according to claim 12 further comprising abattery charger.
 36. A trap according to claim 1 wherein the exit isoperated automatically upon electrocution of an animal.
 37. A trapaccording to claim 36, wherein the exit is actuated either electrically,hydraulically, pneumatically, mechanically or by any combination ofthese.
 38. A trap according to claim 1 wherein the exit is a trapdoor.39. A trap according to claim 1 wherein the electrodes are shielded fromwater flooding from above.
 40. A trap according to claim 1 wherein theelectronic circuit is embedded in a waterproof housing.
 41. A trapaccording to claims 1 further comprising a water-level detector adaptedto send out an electronic signal, in the case water is detected in alevel above a predetermined level, and wherein the electronic circuit isadapted to react in response to an electronic signal from the waterlevel detector by disabling the generation of the high-voltage.
 42. Atrap according to claim 12, wherein the electronic circuit stores anidentification code for the trap.
 43. A trap according to claim 1wherein the means for communicating a surveillance signal comprisesmeans for transmitting a wireless signal to an external unit providedwith a receiver for receiving such a surveillance signal.
 43. A trapaccording to claim 1, further comprising a receiving unit for receivinga command signal from the external unit.
 44. A trap according to claim1, further comprising a receiving unit for receiving a command signalfrom the external unit.
 45. A trap according to claim 43, wherein thewireless signal is an electromagnetic signal.
 46. A trap according toclaim 1 wherein the surveillance signal is only send out upon receivinga request signal.
 47. A trap according to claim 45 wherein theelectromagnetic signal is a radio-signal.
 48. A trap according to claim45, wherein the frequency of the electromagnetic signal is in the range2.2 to 2.8 GHz.
 49. A trap according to claim 1 further comprising meansfor determining the geographical position of the trap.
 50. A trapaccording to claim 1, wherein the surveillance signal containsinformation about at least one of the following particulars: the numberof captured animal, the condition of the battery, the remains of thebait, the position of the trap, and/or an identification code for thetrap.
 51. A trap according to claim 2 wherein the size of the entranceis adjustable.
 52. A trap according to claim 51 wherein the size of theentrance is adjustable via the communication means.
 53. A trap systemcomprising: at least one trap according to claim 1, and at least oneexternal unit comprising: communication means for receiving asurveillance signal from the trap and optionally, for transmitting acommand signal to the trap, and computer processing means adapted inresponse to commands from computer software to read the status of eithera single trap or an ensemble of traps.
 54. A method for electrocuting ananimal comprising the steps of: detecting an animal updating aninformation storage with information relating to a total number ofelectrocutions, and transmitting a surveillance signal to an externalunit, the surveillance signal comprising the information relating to thetotal number of electrocutions.
 55. A method where an electrocuting trapcomprises a water-level detector adapted to send out an electronicsignal, in the case the water level rises above a predetermined level,and wherein an electronic circuit for electrocution is adapted to reactin response to an electronic signal from the water level detector bydisabling the generation of the high-voltage.